Closure for folding paperboard cartons



Feb. 7, 1961 o. w. STONE EI'AL CLOSURE FOR FOLDING PAPERBOARD CARTONS Original Filed Au 6, 1956 '1 ,i llll lmh.

INVEN TOR. OR/SON W. STONE BY LAURI H. CAMPB LL ATTORNEYS CLOSURE FOR FOLDING PAPERBOARD CARTONS Orison W. Stone, Valley Cottage, N.Y., and Laurie H.

Campbell, New London, Conn., 'assignors to Continental Can Company, Inc., New York, N.Y., a corporation of New York Continuation of abandoned application Ser. No. 602,254, Aug. 6, 1956. This application Sept. 22, 1959, Ser. No. 841,489

10 Claims. (Cl. 229-41) The invention relates to a closure for the end of a folding paperboard carton.

Summary In accordance with our invention, a partial closure is formed at the end of a folding carton by means of separate infolding flaps which are interlocked together to hold them in the form of a continuous peripheral flange. The invention is applicable generally to cartons having a tubular body of rectangular form. The flaps may be described as partial end flaps extendingfrom the sides of the tubular body and foldable inwardly to form the aforesaid continuous flange extending around the periphery of the end of the carton. Adjacent end flaps overlap at the corners of the carton, and interlocking tongues and slots are provided in the overlapping portions thereof. The closing of the carton is quickly and easily performed by first folding over the slotted flaps and then the tongued flaps, after which the tongues are snapped through the slots either manually or by suitable mechanical means. The resulting closure is characterized by economy of paperboard stock and the fact that no gluing operation is required.

Description In the drawings wherein we have illustrated the best mode contemplated by us for carrying out our invention: Fig. 1 is a perspective view of a canton embodying our improved closure, the partial end flaps thereof being shown in the positions occupied before they are closed;

Fig. 2 is an end view of the same carton, with three of the flaps fully folded and interlocked, and the fourth flap partially folded;

Fig. 3 is a partial cross sectional view taken as indicated at 33 in Fig. 2, and made to an enlarged scale;

Fig. 4 is a perspective view of one end of a carton having a closure of modified construction; and

Fig. 5 is an end view of this modified construction, with three of the flaps folded and interlocked, and the fourth flap partially folded as in Fig. 2.

Reference will first be made to the preferred embodiment shown in Figs. 1 to 3 inclusive. The carton here illustrated has a body of generally rectangular form, comprising body panels 6, 7, 8 and 9, the glue lap 10 extending from body panel 8 being secured to body panel 9 in the usual fashion to form a flat folded carton which can be erected to the tubular form shown in Fig. 1. Partial end flaps 11, 12, 13 and 14 extend from the sides of the tubular body and are foldable about suitable score lines f to form a continuous flange extending around the periphery of the carton end.

Two opposed flaps 11 and 12 have slots or openings formed by means of cut lines 15. In the specific embodiment described, these out lines are 0 shaped, and fold lines 16 extend across the open ends of the Cs, forming tabs 17 which can be pushed inwardly in the manner indicated in Fig. 3. The remaining two opposed end flaps United States FatentO 13 and 14 are formed with tongues 18 foldable about lines 19 into the position shown in Fig. 3.

In closing the carton described, the slotted end flaps 11 and 12 are first infolded as shown in Fig. 2, and then the tongued end flaps 13 and 14 are infolded. This brings the tongues 18 into positions overlying the respective slots 15, so that the tongues can be pressed through the slots to interlock the overlapping portions of the flaps. The tongues 18 (and the tabs 17) project into the carton at the respective corners thereof to occupy corner spaces made available in the packing of tubular articles, such as .rnetal cans C, Fig. 3.

about diagonally arranged score lines 24. If desired the tongued flaps may have cut out portions 25, so that the continuous flange formed by the end flaps will be of uniform width around the periphery of the carton end.

Partial closures of the forms we have described may be provided at one or both ends of the carton as desired.

This application is a continuation of the application of Stone and Campbell, Serial No. 602,254 .filed August 6, 1956, now abandoned.

The termsand expressions which we have employed are used in a descriptive and not a limiting sense, and we have no intention of excluding such equivalents of the invention described, or of portions thereof, as fall within the scope of the claims.

We claim:

1. A carton construction comprising a tubular body of generally rectangular form having four body panels, a partial end flap extending from each side of each body panel, said partial end flaps being foldable inwardly to form a continuous flange extending around the periphery of each carton end with adjacent end flaps overlapping at the corners of the carton, and a construction for locking the overlapping portions of said end flaps together when the carton is loaded which includes a tongue projecting from each corner of one of each pair of overlapping end flaps and a slot in the overlapped portions of the corresponding end flap, each tongue being folded bodily inwardly of the carton about the edge of its complementary slot when the end flaps are in their normal closed positions at right angles to the sides of the carton body.

2. The carton construction in accordance with claim 1,

in which each tongue has shoulders formed on both side edges thereof, at least each of said shoulders of one tongue being formed by a cut that extends into the flap to which the said tongue is integrally connected.

3. A carton construction comprising a tubular body of generally rectangular form having four body panels, a partial end flap extending from each side of each body panel, said partial end flaps being foldable inwardly to form a continuous flange extending around the periphery of each carton end with adjacent end flaps overlapping at the corners of the carton, and a construction for locking the overlapping portions of said end flaps together when the carton is loaded which includes a tongue projecting from each corner of alternate end flaps at each end of the carton and complementary slots in the remaining end flaps at that end of the carton, said complementary slots being formed by cut lines including C-shaped cuts forming tabs foldable along lines extending across and connecting the open ends of the Cs, the depth of said tabs between such lines of folding and the backs of the 0's being at least equal to the depth of the tongues whereby the outer ends of the tongues lie within the area. of said tabs when the end flaps are in their normal closed positions'at' right angles to the sides of the carton body.

4. The carton construction in accordance with claim 3, in which each tongue has shoulders formed on both side edges thereof, at least each of said shoulders of one tongue being formed by a cut that extends into the flap to which the said tongue is integrally connected.

5. A paperboard blank for a folding'carton having-a tubular body of general rectangular form comprising four bodypanels arranged'side by side with fold lines between adjacent panels, a glue flap extending from the outer side edge of one of the panels at the edge of the blank, partial end flaps extending from each end of'each side panel, a tongue projecting from-each corner of alternate end flaps and complementary'slots in the'remaining end flaps,- said complementary slots being formed by cut lines including G-shaped cuts formingtabs foldable'alo'ng line's extending across and connecting the open ends of the Us; the depth of saidtabsbetween such lines; of folding and the backs of the Us being at least equal to the depth of the tongues.

6. A paperboard blankin accordanc'e with claim 5 in which each tongue has shoulders formed on both side edges thereof, at least one of said shoulders of one tongue being formed by a cut that extends into the flap to which said tongue is integrally connected.

7. A package comprising a plurality of cans arranged in at least one row, a tubular carton having four main body panels, a partial end flap extending inwardly from each end of each of the main body panels and disposed substantially perpendicular to the plane of its body panel so that the end portions of adjacent partial end flaps are in overlapping-relation, said partial end fiiaps being dimensioned so that there is a substantial centrally located opening-at each end-oi the package, a tongue extending from each overlappingTendflportion-and complementary slots in the body of thefrelated overlapped end portion aligned with its corresponding tongue, such a tongue andsloti arrangement being provided at each area otoverlapi of the partialend flaps, each tongue passing inwardly through its complementary slot into the corner space between the end can and the corner of the carton and being angularly disposed relative to the plane of the partial end flaps such that the free end-of the tongue is spaced a substantial distance from the inner face of the adjacent partial end flap, each of said tongues having integral shoulders which extend laterally on both sides of the complementary slots and engage the inner face of the adjacent partial end flaps; thereby maintaining the angular disposition of its tongue to prevent the accidental dislodgemeut thereof from the slot.

8. A package in accordance with claim 7, in which said tongues are disposed at an angle of more than relative to the plane oftherpartial end flaps.

9. A package in accordance with claim 7, in which at leastone of the shoulders of each tongue is formed by a cut that' extends into the partial end flap to which'the tongue is integrally connected.

10. A rectangular carton having. similar partially closed ends to enclose axially upright cylindrical cans with atspace in the corners of the carton, comprising-four panels hinged along fold linesand forming top and hottom-walls and two side walls, a lateral fiap extending from each of the side wall panels forming' two inner end flaps at each end of the carton, a lateral flap extending from each end of the top wall panel and eachend of the bottom wall panel forming two outer end flaps at each end of the carton with the ends of the outer end flaps overlapping the ends of the inner end flaps, the two corner portions. of each of the. outer. end flaps' having a tongue, and the two corner portions of, each of the inner end fiapshaving a coacting notch that lies adjacent the space in the corners of the carton to receive and hold a corresponding tongue to form secured end walls of the carton and retain the cans therein,vsaid tongue and notch engagement being characterized by the. fact that the tongue is as long as the. notch and initially. overlies said notch and has a pointed head portion widerthan its base portion, said notch being formed from slitsformingbendable "tabs-defining'an opening which receives the tongue,

said tongue in operative position projectinginto the cor.-

ner ofthecarton atanabruptangle to the-plane of the.

end. face of the'carton, and said fiaps in locked position only partiallyclosing each end of the carton.

References Cite'din the file of this patent UNITED STATES PATENTS 2,354,098 Bamber July 18, 1944 2,796,979 Buttery June 25, 1957 FOREIGN PATENTS 398,044 Great Britain Sept. 7, 1933 silk UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No 2,970,741 February 7, 1961 Orison W, Stone et a1.

It is hereby certified'that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, line 51, and column 3, line 5, for "each,

each occurrence, read one same lines for "one", each occurrence, read each si qfifa" and sealedthis 11th day of July 1961.,

(SEAL) Attcst:

ERNEST W. SWIDER DAVID'L. LADD Attesting Officer Commissioner of Patents 

